Regions
Northwest Inland.
New slabs will likely form during Thursday night's storm. Expect to find the deepest and touchiest deposits in cross-loaded and lee terrain features.
Confidence
Moderate - Forecast snowfall amounts are uncertain
Weather Forecast
THURSDAY NIGHT: Cloudy with snowfall, accumulation 5 to 10 cm, strong southwest wind, alpine temperature -8 C.FRIDAY: Cloudy with snowfall, accumulation 1 to 5 cm, light to moderate southwest wind, alpine temperature -8 C.SATURDAY: Early-morning snowfall and clearing over the day, accumulation 1 to 3 cm, light east wind, alpine temperature -16 C.SUNDAY: Clear skies, light to moderate east wind, alpine temperature -16 C.
Avalanche Summary
A few small wind slab avalanches were triggered by skiers and naturally on Wednesday. They were on all aspects, in steep terrain, and at treeline and alpine elevations. The slabs were generally 10 to 20 cm deep.
Snowpack Summary
Thursday night into Friday's storm is expected to deliver another 10 to 15 cm of snow, which will add to the 5 to 10 cm received on Tuesday. Strong southwest wind during both of these storms will form wind slabs in cross-loaded and lee terrain features in exposed areas. In sheltered areas at and below treeline, this new snow fell onto pockets of feathery surface hoar crystals and soft, faceted snow.In the south of the region, the remainder of the snowpack is well-settled. In the north of the region, around 50 cm of snow may overly a weak layer of surface hoar or faceted grains.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.